Although a variety of devices are available for executing lateral and longitudinal cuts on workpieces (some of which utilize portable power saws) generally such devices have a frame or base attached to a support stand having a plurality of supporting legs. A small, essentially rectangular platform is afixed to the frame or base defining a workpiece support surface. An arm or saw guide is usually secured by a support means to the frame and is disposed over the workpiece support surface. While the saw is usually slidable along the arm or saw guide, it is, generally, in some way permanently attached to it and forms an integral part of the device. This combination of components makes such devices bulky, heavy, difficult to move and awkward to transport. Furthermore, the relatively small workpiece support platforms of such devices do not conveniently lend themselves to extension. It is desirable, however, when cutting an elongated workpiece, to have an extended surface supporting such a workpiece over its entire length to prevent it from jackknifing and to keep the ends from falling when cut. Such an extended workpiece support surface, by means of markings on it, may also serve as a gauge to quickly measure the desired lengths to be cut. Moreover, once the workpiece support platform of such a prior art device is extended, the device is then more or less attached to the extension and is inconvenient to move.
In addition, it is a known characteristic of such a commonly used sawing device as the standard fixed arm radial arm saw, that a cut is executed with it by drawing the saw forwardly across the workpiece. Because of the direction of the saw blade rotation, the saw has the objectionable tendency to feed itself, climb the workpiece and jamb, thus stalling the motor, so that considerable care and effort must be exercised when executing a cut. Additional care must be taken, upon completion of a cut, to return the saw along the kerf to its rearward position to permit the safe removal, replacement and positioning of the workpiece. The fixed arm, however, remains over the workpiece support surface more or less in the way of the operator.
The objects of the present invention are, therefore, to provide a sawing device which is of light weight and easily portable and which is convenient to set up and use in conjunction with a simply constructed, extended workpiece support bench; a device which utilizes a conventional portable circular power saw which may be easily mounted on, and removed from it, thus reducing the weight of the device for portability and also eliminating duplication by permitting the use of the same saw for other purposes; a sawing device in which the saw may be mutually reciprocated with the support arm and also be pivotably attached to it so that the saw may be drawn forwardly above the workpiece, then plunged down and pushed rearwardly into the cut, thereby eliminating self-feeding. It may then be tilted upwardly out of the way to clear the work area for removal, placement and positioning of the workpiece.
It is, of course, desirable to provide on such a sawing device means for automatically retracting the saw blade guard as the saw is lowered into a cut and for permitting the guard to return around the saw blade as the saw is tilted upwardly.
It is also an object of the present invention to provide a sawing device, with the aforementioned features, which is sufficiently versatile to perform all desirable cuts, uncomplicated to manufacture and use, sturdily constructed, durable, yet sufficiently compact to be convenient to transport.